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Pusterla N, Bain F, James K, Mapes S, Kenelty K, Barnett DC, Gaughan E, Craig B, Chappell DE, Vaala W. Frequency of molecular detection of equine herpesvirus-4 in nasal secretions of 3028 horses with upper airway infection. Vet Rec 2017; 180:593. [DOI: 10.1136/vr.104240] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/16/2017] [Indexed: 11/04/2022]
Affiliation(s)
- N. Pusterla
- Department of Medicine and Epidemiology; School of Veterinary Medicine, University of California; Davis California USA
| | - F. Bain
- Merck Animal Health; Summit, New Jersey USA
| | - K. James
- Department of Medicine and Epidemiology; School of Veterinary Medicine, University of California; Davis California USA
| | - S. Mapes
- Department of Medicine and Epidemiology; School of Veterinary Medicine, University of California; Davis California USA
| | - K. Kenelty
- Department of Medicine and Epidemiology; School of Veterinary Medicine, University of California; Davis California USA
| | | | - E. Gaughan
- Merck Animal Health; Summit, New Jersey USA
| | - B. Craig
- Merck Animal Health; Summit, New Jersey USA
| | | | - W. Vaala
- Merck Animal Health; Summit, New Jersey USA
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Pusterla N, Kass P, Mapes S, Akana N, Vaala W, Barnett D, MacKenzie C. Surveillance program for Equine Influenza Virus in the United States (2010-2013). J Equine Vet Sci 2016. [DOI: 10.1016/j.jevs.2016.02.004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Pusterla N, Mapes S, Akana N, Barnett C, MacKenzie C, Gaughan E, Craig B, Chappell D, Vaala W. Prevalence factors associated with equine herpesvirus type 1 infection in equids with upper respiratory tract infection and/or acute onset of neurological signs from 2008 to 2014. Vet Rec 2015; 178:70. [PMID: 26607427 DOI: 10.1136/vr.103424] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/02/2015] [Indexed: 11/04/2022]
Abstract
The objective of the present case-control study was to determine prevalence factors associated with the detection of equine herpesvirus type 1 (EHV-1) by quantitative PCR (qPCR) in horses presented to veterinarians with clinical signs related to an upper respiratory tract infection and/or acute onset of neurological disease from March 2008 to December 2014. Nasal secretions and whole blood from 4228 equids with acute onset of fever, respiratory signs and/or neurological deficits were tested by qPCR for EHV-1. Categorical analyses were performed to determine the association between observations and EHV-1. A total of 117/4228 (2.7 per cent) equids tested qPCR-positive for EHV-1, with most of the isolates belonging to the non-neuropathogenic genotype (N752). EHV-1 PCR-positive equids were over-represented in racing horses. Depression, anorexia, nasal discharge and coughing were significantly less frequently reported in the EHV-1 qPCR-positive equids compared with the EHV-1 qPCR-negative cases. Neurological deficits were more frequently reported in the EHV-1 qPCR-positive cases. This study provides contemporary information on the frequency of EHV-1 detection by qPCR in blood and nasal secretions from horses with fever, respiratory signs and neurological deficits.
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Affiliation(s)
- N Pusterla
- Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California, Davis, CA, USA
| | - S Mapes
- Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California, Davis, CA, USA
| | - N Akana
- Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California, Davis, CA, USA
| | - C Barnett
- Merck Animal Health, Summit, NJ, USA
| | | | - E Gaughan
- Merck Animal Health, Summit, NJ, USA
| | - B Craig
- Merck Animal Health, Summit, NJ, USA
| | | | - W Vaala
- Merck Animal Health, Summit, NJ, USA
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Pusterla N, Holzenkaempfer N, Mapes S, Kass P. Prevalence of equine coronavirus in nasal secretions from horses with fever and upper respiratory tract infection. Vet Rec 2015; 177:289. [PMID: 26260064 DOI: 10.1136/vr.103263] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/21/2015] [Indexed: 11/04/2022]
Affiliation(s)
- N Pusterla
- Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California, Davis, CA 95616, USA
| | - N Holzenkaempfer
- Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California, Davis, CA 95616, USA
| | - S Mapes
- Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California, Davis, CA 95616, USA
| | - P Kass
- Department of Population Health and Reproduction, School of Veterinary Medicine, University of California, Davis, CA 95616, USA
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Giannitti F, Diab S, Mete A, Stanton JB, Fielding L, Crossley B, Sverlow K, Fish S, Mapes S, Scott L, Pusterla N. Necrotizing Enteritis and Hyperammonemic Encephalopathy Associated With Equine Coronavirus Infection in Equids. Vet Pathol 2015; 52:1148-56. [PMID: 25648965 DOI: 10.1177/0300985814568683] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Equine coronavirus (ECoV) is a Betacoronavirus recently associated clinically and epidemiologically with emerging outbreaks of pyrogenic, enteric, and/or neurologic disease in horses in the United States, Japan, and Europe. We describe the pathologic, immunohistochemical, ultrastructural, and molecular findings in 2 horses and 1 donkey that succumbed to natural infection with ECoV. One horse and the donkey (case Nos. 1, 3) had severe diffuse necrotizing enteritis with marked villous attenuation, epithelial cell necrosis at the tips of the villi, neutrophilic and fibrinous extravasation into the small intestinal lumen (pseudomembrane formation), as well as crypt necrosis, microthrombosis, and hemorrhage. The other horse (case No. 2) had hyperammonemic encephalopathy with Alzheimer type II astrocytosis throughout the cerebral cortex. ECoV was detected by quantitative polymerase chain reaction in small intestinal tissue, contents, and/or feces, and coronavirus antigen was detected by immunohistochemistry in the small intestine in all cases. Coronavirus-like particles characterized by spherical, moderately electron lucent, enveloped virions with distinct peplomer-like structures projecting from the surface were detected by negatively stained transmission electron microscopy in small intestine in case No. 1, and transmission electron microscopy of fixed small intestinal tissue from the same case revealed similar 85- to 100-nm intracytoplasmic particles located in vacuoles and free in the cytoplasm of unidentified (presumably epithelial) cells. Sequence comparison showed 97.9% to 99.0% sequence identity with the ECoV-NC99 and Tokachi09 strains. All together, these results indicate that ECoV is associated with necrotizing enteritis and hyperammonemic encephalopathy in equids.
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Affiliation(s)
- F Giannitti
- California Animal Health and Food Safety Laboratory, School of Veterinary Medicine, University of California, Davis, CA, USA Veterinary Diagnostic Laboratory, College of Veterinary Medicine, University of Minnesota, Saint Paul, MN, USA
| | - S Diab
- California Animal Health and Food Safety Laboratory, School of Veterinary Medicine, University of California, Davis, CA, USA
| | - A Mete
- California Animal Health and Food Safety Laboratory, School of Veterinary Medicine, University of California, Davis, CA, USA
| | - J B Stanton
- Department of Veterinary Microbiology and Pathology and Washington Animal Disease Diagnostic Laboratory, College of Veterinary Medicine, Washington State University, Pullman, WA, USA
| | - L Fielding
- Loomis Basin Equine Medical Center, Loomis, CA, USA
| | - B Crossley
- California Animal Health and Food Safety Laboratory, School of Veterinary Medicine, University of California, Davis, CA, USA
| | - K Sverlow
- California Animal Health and Food Safety Laboratory, School of Veterinary Medicine, University of California, Davis, CA, USA
| | - S Fish
- California Animal Health and Food Safety Laboratory, School of Veterinary Medicine, University of California, Davis, CA, USA
| | - S Mapes
- Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California, Davis, CA, USA
| | - L Scott
- Idaho Equine Hospital, Nampa, ID, USA
| | - N Pusterla
- Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California, Davis, CA, USA
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Pusterla N, Kass PH, Mapes S, Wademan C, Akana N, Barnett C, MacKenzie C, Vaala W. Voluntary surveillance program for equine influenza virus in the United States from 2010 to 2013. J Vet Intern Med 2015; 29:417-22. [PMID: 25586234 PMCID: PMC4858095 DOI: 10.1111/jvim.12519] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2014] [Revised: 10/15/2014] [Accepted: 11/10/2014] [Indexed: 11/30/2022] Open
Abstract
Background Recent surveillance studies for equine respiratory viruses have shown that equine influenza virus (EIV) continues to be a prevalent respiratory virus of equids throughout the United States and Europe. Objectives To gain a better understanding of the prevalence and epidemiology of EIV shed by horses, mules and donkeys in the United States from March 2010 to November 2013. Animals 2,605 equids. Methods Nasal secretions from index cases with acute onset of respiratory disease were tested by qPCR for EIV. Multilevel logistic regression was used to model the association between EIV status and prevalence factors. Furthermore, observations from EIV‐positive study horses were compared to previous data from March 2008 to February 2010. Results A total of 230 (9.7%) index cases tested qPCR positive for EIV. A higher‐than‐expected proportion of EIV qPCR‐positive horses occurred in the 1–5, 6–10, and 11–15 age groups when compared to the <1 year of age group. Fever, nasal discharge and coughing were positively associated with EIV‐positive horses. EIV qPCR‐positive study cases were significantly older and more often vaccinated against EIV compared to EIV qPCR‐positive animals from the 2008‐2010 study period. Conclusions and Clinical Importance This study provides valuable and contemporary information on the frequency of EIV detected by qPCR in the United States. The results also underscore that older and previously vaccinated horses were susceptible to EIV.
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Affiliation(s)
- N Pusterla
- Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California, Davis, CA
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Estell KE, Dawson DR, Magdesian KG, Swain E, Laing ST, Siso S, Mapes S, Pusterla N. Quantitative molecular viral loads in 7 horses with naturally occurring equine herpesvirus-1 infection. Equine Vet J 2014; 47:689-93. [PMID: 25212737 DOI: 10.1111/evj.12351] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2013] [Accepted: 08/10/2014] [Indexed: 11/28/2022]
Abstract
REASONS FOR PERFORMING STUDY Data associating quantitative viral load with severity, clinical signs and survival in equine herpesvirus-1 myeloencephalopathy (EHM) have not been reported. OBJECTIVES To report the clinical signs, treatment, and temporal progression of viral loads in 7 horses with naturally occurring EHM and to examine the association of these factors with survival. STUDY DESIGN Retrospective case series. METHODS The population included 7 horses with EHM presented to the University of California, Davis William R. Pritchard Veterinary Medical Teaching Hospital from May to September 2011. Horses were graded using a neurological grading scale. Daily quantitative PCR was performed on nasal secretions and whole blood. Treatment, survival, outcome and histopathology were reported. RESULTS At presentation, one horse was neurological grade 5/5, 3 were grade 4/5 and 3 were grade 3/5. All were treated with anti-inflammatory drugs, valacyclovir and management in a sling if necessary. All were infected with equine herpesvirus-1 of DNA polymerase D752 genotype. Peak viral load in nasal secretions and blood of 5 survivors ranged from 6.9 × 10(3) to 2.81 × 10(5) (median 5.11 × 10(4) ) and from 143 to 4340 gB gene copies/million eukaryotic cells (median 3146), respectively. The 2 nonsurvivors presented with grade 3/5 neurological signs and progressed to encephalopathy. Peak viral load was higher in nonsurvivors, with levels in nasal secretions of 1.9 × 10(9) and 2.2 × 10(9) and in blood of 2.05 × 10(4) and 1.02 × 10(5) gB gene copies/million eukaryotic cells. Case fatality was 2/7. CONCLUSIONS Nonsurvivors had viral loads 1000-fold higher in nasal secretions and 10-fold higher in blood than survivors. There was no relationship between severity of clinical signs at presentation and survival. Thus, encephalopathy and high viral load were negatively associated with survival in this population. Further research should be performed to determine whether high viral loads are associated with encephalopathy and poor prognosis. The Summary is available in Chinese - see Supporting information.
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Affiliation(s)
- K E Estell
- William R. Pritchard Veterinary Medical Teaching Hospital, University of California, Davis, USA
| | - D R Dawson
- William R. Pritchard Veterinary Medical Teaching Hospital, University of California, Davis, USA
| | - K G Magdesian
- William R. Pritchard Veterinary Medical Teaching Hospital, University of California, Davis, USA
| | - E Swain
- William R. Pritchard Veterinary Medical Teaching Hospital, University of California, Davis, USA
| | - S T Laing
- William R. Pritchard Veterinary Medical Teaching Hospital, University of California, Davis, USA
| | - S Siso
- William R. Pritchard Veterinary Medical Teaching Hospital, University of California, Davis, USA
| | - S Mapes
- William R. Pritchard Veterinary Medical Teaching Hospital, University of California, Davis, USA
| | - N Pusterla
- William R. Pritchard Veterinary Medical Teaching Hospital, University of California, Davis, USA
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Harms C, Mapes S, Akana N, Coatti Rocha D, Pusterla N. Detection of modified-live equine intranasal vaccine pathogens in adult horses using quantitative PCR. Vet Rec 2014; 175:510. [PMID: 25274853 DOI: 10.1136/vr.102592] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Affiliation(s)
- C Harms
- Department of Veterinary Medicine and Epidemiology, School of Veterinary Medicine, University of California, Davis, CA 95616, USA
| | - S Mapes
- Department of Veterinary Medicine and Epidemiology, School of Veterinary Medicine, University of California, Davis, CA 95616, USA
| | - N Akana
- Department of Veterinary Medicine and Epidemiology, School of Veterinary Medicine, University of California, Davis, CA 95616, USA
| | - D Coatti Rocha
- Department of Veterinary Medicine and Epidemiology, School of Veterinary Medicine, University of California, Davis, CA 95616, USA
| | - N Pusterla
- Department of Veterinary Medicine and Epidemiology, School of Veterinary Medicine, University of California, Davis, CA 95616, USA
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Pusterla N, Estell K, Mapes S, Wademan C. Detection of clade 2 equine influenza virus in an adult horse recently imported to the USA. EQUINE VET EDUC 2014. [DOI: 10.1111/eve.12159] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
- N. Pusterla
- Department of Veterinary Medicine and Epidemiology; School of Veterinary Medicine; University of California; Davis USA
| | - K. Estell
- Department of Veterinary Medicine and Epidemiology; School of Veterinary Medicine; University of California; Davis USA
| | - S. Mapes
- Department of Veterinary Medicine and Epidemiology; School of Veterinary Medicine; University of California; Davis USA
| | - C. Wademan
- Department of Veterinary Medicine and Epidemiology; School of Veterinary Medicine; University of California; Davis USA
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Sampieri F, Alcorn J, Allen AL, Clark CR, Vannucci FA, Pusterla N, Mapes S, Ball KR, Dowling PM, Thompson J, Bernstein LR, Gebhart CJ, Hamilton DL. Pharmacokinetics of gallium maltolate in Lawsonia intracellularis-infected and uninfected rabbits. J Vet Pharmacol Ther 2014; 37:486-99. [PMID: 24628462 DOI: 10.1111/jvp.12114] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2013] [Accepted: 01/14/2014] [Indexed: 11/27/2022]
Abstract
Oral gallium maltolate (GaM) pharmacokinetics (PK) and intestinal tissue (IT) concentrations of elemental gallium ([Ga]) and iron ([Fe]) were investigated in a rabbit model of equine proliferative enteropathy (EPE). New Zealand white does (uninfected controls and EPE-infected, n = 6/group) were given a single oral GaM dose (50 mg/kg). Serial blood samples were collected from 0 to 216 h post-treatment (PT) and IT samples after euthanasia. Serology, qPCR, and immunohistochemistry confirmed, or excluded, EPE. Blood and IT [Ga] and [Fe] were determined using inductively coupled plasma-mass spectrometry. PK parameters were estimated through noncompartmental approaches. For all statistical comparisons on [Ga] and [Fe] α = 5%. The Ga log-linear terminal phase rate constant was lower in EPE rabbits vs. uninfected controls [0.0116 ± 0.004 (SD) vs. 0.0171 ± 0.0028 per hour; P = 0.03]; but half-life (59.4 ± 24.0 vs. 39.4 ± 10.8 h; P = 0.12); Cmax (0.50 ± 0.21 vs. 0.59 ± 0.42 μg/mL; P = 0.45); tmax (1.75 ± 0.41 vs. 0.9 ± 0.37 h; P = 0.20); and oral clearance (6.743 ± 1.887 vs. 7.208 ± 2.565 L/h; P = 0.74) were not. IT's [Ga] and [Fe] were higher (P < 0.0001) in controls. In conclusion, although infection reduces IT [Ga] and [Fe], a 48 h GaM dosing interval is appropriate for multidose studies in EPE rabbits.
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Affiliation(s)
- F Sampieri
- Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, SK, Canada
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Pusterla N, Byrne BA, Mapes S, Akana N, Wademan C, Fielding LC, Slovis N, Elam T, Magdesian KG. Investigation of the use of pooled faecal and environmental samples following an enrichment step for the detection of Salmonella enterica by real-time PCR. Vet Rec 2014; 174:252. [PMID: 24570410 DOI: 10.1136/vr.101975] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Affiliation(s)
- N Pusterla
- Department of Veterinary Medicine and Epidemiology, School of Veterinary Medicine, University of California, Davis, CA 95616, USA
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Pusterla N, Sanchez-Migallon Guzman D, Vannucci F, Mapes S, White A, DiFrancesco M, Gebhart C. Transmission of Lawsonia intracellularis to weanling foals using feces from experimentally infected rabbits. Vet J 2013; 195:241-3. [DOI: 10.1016/j.tvjl.2012.05.028] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2012] [Revised: 05/23/2012] [Accepted: 05/29/2012] [Indexed: 10/28/2022]
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Pusterla N, Mapes S, Wademan C, White A, Ball R, Sapp K, Burns P, Ormond C, Butterworth K, Bartol J, Magdesian KG. Emerging outbreaks associated with equine coronavirus in adult horses. Vet Microbiol 2012; 162:228-31. [PMID: 23123176 PMCID: PMC7117461 DOI: 10.1016/j.vetmic.2012.10.014] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2012] [Revised: 09/26/2012] [Accepted: 10/05/2012] [Indexed: 11/08/2022]
Abstract
The purpose of this study was to describe clinical, hematological and fecal PCR results from 161 horses involved in outbreaks associated with ECoV. The outbreaks happened at four separate boarding facilities between November 2011 and April 2012 in the States of CA, TX, WI and MA. Following the molecular detection of ECoV in the feces from the initial index cases, the remaining herdmates were closely observed for the development of clinical signs. Fecal samples were collected from sick and healthy horses for the PCR detection of ECoV. All four outbreaks involved primarily adult horses. Fifty-nine horses developed clinical signs with 12–16 sick horses per outbreak. The main clinical signs reported were anorexia, lethargy and fever. Four horses from 3 different outbreaks were euthanized or died due to rapid progression of clinical signs. The cause of death could not be determined with necropsy evaluation in 2 horses, while septicemia secondary to gastrointestinal translocation was suspected in 2 horses. Blood work was available from 10 horses with clinical disease and common hematological abnormalities were leucopenia due to neutropenia and/or lymphopenia. Feces were available for ECoV testing by real-time PCR from 44 and 96 sick and healthy horses, respectively. 38/44 (86%) horses with abnormal clinical signs tested PCR positive for ECoV, while 89/96 (93%) healthy horses tested PCR negative for ECoV. The overall agreement between clinical status and PCR detection of ECoV was 91%. The study results suggest that ECoV is associated with self-limiting clinical and hematological abnormalities in adult horses.
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Affiliation(s)
- N Pusterla
- Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California, Davis, CA 95616, USA.
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Pusterla N, Mapes S, Wademan C, White A, Hodzic E. Investigation of the role of lesser characterized respiratory viruses associated with upper respiratory tract infections in horses. J Equine Vet Sci 2012. [DOI: 10.1016/j.jevs.2012.08.059] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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15
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Pusterla N, Sanchez-Migallon Guzman D, Vannucci F, Mapes S, White A, DiFrancesco M, Gebhart C. Transmission of Lawsonia intracellularis to weanling foals using feces from experimentally infected rabbits. J Equine Vet Sci 2012. [DOI: 10.1016/j.jevs.2012.08.087] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Pusterla N, Mapes S, Wademan C, White A, Estell K, Swain E. Investigation of the role of mules as silent shedders of equine herpesvirus-1 during an outbreak of equine herpesvirus-1 myeloencephalopathy in California. J Equine Vet Sci 2012. [DOI: 10.1016/j.jevs.2012.08.138] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Pusterla N, Mapes S, Wademan C, White A, Estell K, Swain E. Investigation of the role of mules as silent shedders of EHV-1 during an outbreak of EHV-1 myeloencephalopathy in California. Vet Rec 2012; 170:465. [PMID: 22472540 DOI: 10.1136/vr.100598] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- N Pusterla
- Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California, Davis, CA 95616, USA.
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Palmero J, Pusterla N, Cherry NA, Kasten RW, Mapes S, Boulouis HJ, Breitschwerdt EB, Chomel BB. Experimental infection of horses with Bartonella henselae and Bartonella bovis. J Vet Intern Med 2012; 26:377-83. [PMID: 22356473 DOI: 10.1111/j.1939-1676.2012.00890.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2011] [Revised: 12/11/2011] [Accepted: 01/09/2012] [Indexed: 12/01/2022] Open
Abstract
BACKGROUND Experimental infection of horses with Bartonella species is not documented. OBJECTIVES Determine clinical signs, hematologic changes, duration of bacteremia, and pattern of seroconversion in Bartonella henselae or Bartonella bovis-inoculated horses. ANIMALS Twelve (2 groups of 6) randomly selected healthy adult horses seronegative and culture negative for Bartonella spp. METHODS Experimental/observational study: Group I: B. henselae or saline control was inoculated intradermally into 4 naïve and 2 sentinel horses, respectively. Group II: same design was followed by means of B. bovis. Daily physical examinations, once weekly CBC, immunofluorescent antibody assay serology, real-time polymerase chain reaction (PCR), and twice weekly blood cultures were performed for 6 weeks and at postinoculation day 80 and 139. Bartonella alpha-Proteobacteria growth medium (BAPGM) enrichment blood culture was performed for horses that seroconverted to B. henselae antigens. RESULTS Transient clinical signs consistent with bartonellosis occurred in some Bartonella-inoculated horses, but hematological alterations did not occur. Three B. henselae-inoculated horses seroconverted, whereas 1 B. bovis-inoculated horse was weakly seropositive. In Group I, B. henselae was amplified and sequenced from BAPGM blood culture as well as a subculture isolate from 1 horse, blood from a 2nd horse, and BAPGM blood culture from a 3rd horse although a subculture isolate was not obtained. All sentinels remained PCR, culture, and serology negative. CONCLUSIONS Detection of Bartonella sp. in blood after experimental inoculation supports bacteremia and seroconversion. Culture with BAPGM may be required to detect Bartonella sp. Although mild clinical signs followed acute infection, no long-term effects were noted for 2 years postinoculation.
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Affiliation(s)
- J Palmero
- Veterinary Medical Teaching Hospital, School of Veterinary Medicine, University of California, Davis, CA 95616, USA.
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Teglas MB, Mapes S, Hodzic E, Nieto NC. Co-infection of Ornithodoros coriaceus with the relapsing fever spirochete, Borrelia coriaceae, and the agent of epizootic bovine abortion. Med Vet Entomol 2011; 25:337-343. [PMID: 21410735 DOI: 10.1111/j.1365-2915.2011.00952.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
The soft tick, Ornithodoros coriaceus (Koch) (Acari: Argasidae), is a common mammalian parasite of livestock in many arid regions of the western U.S.A. The tick is a known vector of the undescribed bacterial pathogen that causes epizootic bovine abortion (EBA), which results in late-term abortions in beef cattle and subsequent economic loss, which can be considerable, to producers. A second reported bacterial pathogen, Borrelia coriaceae, a member of the relapsing fever complex, has also been identified in this tick and was at one time hypothesized to be the aetiological agent of EBA. In order to test whether bacterial infections in ticks overlapped geographically and to determine the prevalence of co-infection in O. coriaceus populations, we used molecular methods to detect bacterial DNA from ticks collected from a wide variety of habitats in California, Nevada and Oregon. Of the 15 sites at which ticks tested positive for the agent of EBA (aoEBA), eight also contained ticks positive for Borrelia spp. by polymerase chain reaction assay. Additionally, two ticks were co-infected; both of these were collected from the same location. Univariate risk analysis indicated the presence of juniper-dominated habitat at the collection site and geographic location to be significantly associated with infection of the tick vector by either pathogen.
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Affiliation(s)
- M B Teglas
- Department of Animal Biotechnology, University of Nevada-Reno, NV 89957, U.S.A.
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Pusterla N, Kass PH, Mapes S, Johnson C, Barnett DC, Vaala W, Gutierrez C, McDaniel R, Whitehead B, Manning J. Surveillance programme for important equine infectious respiratory pathogens in the USA. Vet Rec 2011; 169:12. [PMID: 21676986 DOI: 10.1136/vr.d2157] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
The prevalence and epidemiology of important viral (equine influenza virus [EIV], equine herpesvirus type 1 [EHV-1] and EHV-4) and bacterial (Streptococcus equi subspecies equi) respiratory pathogens shed by horses presented to equine veterinarians with upper respiratory tract signs and/or acute febrile neurological disease were studied. Veterinarians from throughout the USA were enrolled in a surveillance programme and were asked to collect blood and nasal secretions from equine cases with acute infectious upper respiratory tract disease and/or acute onset of neurological disease. A questionnaire was used to collect information pertaining to each case and its clinical signs. Samples were tested by real-time PCR for the presence of EHV-1, EHV-4, EIV and S equi subspecies equi. A total of 761 horses, mules and donkeys were enrolled in the surveillance programme over a 24-month study period. In total, 201 (26.4 per cent) index cases tested PCR-positive for one or more of the four pathogens. The highest detection rate was for EHV-4 (82 cases), followed by EIV (60 cases), S equi subspecies equi (49 cases) and EHV-1 (23 cases). There were 15 horses with double infections and one horse with a triple infection. The detection rate by PCR for the different pathogens varied with season and with the age, breed, sex and use of the animal.
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Affiliation(s)
- N Pusterla
- Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California, Davis, CA 95616, USA.
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Pusterla N, Mapes S, Wilson WD. Prevalence of equine herpesvirus type 1 in trigeminal ganglia and submandibular lymph nodes of equids examined postmortem. Vet Rec 2010; 167:376-8. [PMID: 20817899 DOI: 10.1136/vr.c3748] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
The objective of this study was to detect and characterise the biovar of equine herpesvirus type 1 (EHV-1) from submandibular lymph nodes (SMLNs) and trigeminal ganglia from 153 equids undergoing routine postmortem examination for various medical and surgical reasons. A combination of nucleic acid precipitation and preamplification steps was used to increase the analytical sensitivity of the analysis. The presence of latent EHV-1 was determined when tissue samples were PCR-positive for the glycoprotein B (gB) gene and the DNA polymerase (ORF 30) gene of EHV-1 in the absence of detectable late structural protein gene (gB gene) mRNA. The SMLNs of five of the study animals (3.3 per cent) were PCR-positive for the gB gene of EHV-1. Two SMLNs carried a latent neurotropic strain of the virus, whereas three SMLNs were PCR-positive for both neurotropic and non-neurotropic EHV-1. A total of 30 trigeminal ganglia collected from 19 horses were PCR-positive for the gB gene of EHV-1. Nine trigeminal ganglia harboured either latent non-neurotropic or neurotropic EHV-1 strains. Twelve trigeminal ganglia contained both latent neurotropic and non-neurotropic EHV-1. The prevalence and distribution of EHV-1 biovars among the study horses appeared to be influenced by their breed and the type of tissue tested.
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Affiliation(s)
- N Pusterla
- Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California, Davis, CA 95616, USA.
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Pusterla N, Hussey S, Mapes S, Johnson C, Collier J, Hill J, Lunn D, Wilson W. Molecular Investigation of the Viral Kinetics of Equine Herpesvirus-1 in Blood and Nasal Secretions of Horses after Corticosteroid-Induced Recrudescence of Latent Infection. J Vet Intern Med 2010; 24:1153-7. [DOI: 10.1111/j.1939-1676.2010.0554.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
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Sykes J, Marks S, Mapes S, Schultz R, Pollard R, Tokarz D, Pesavento P, Lindsay L, Foley J. Salmon Poisoning Disease in Dogs: 29 Cases. J Vet Intern Med 2010; 24:504-13. [DOI: 10.1111/j.1939-1676.2010.0493.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
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Pusterla N, Wattanaphansak S, Mapes S, Collier J, Hill J, Difrancesco M, Gebhart C. Oral infection of weanling foals with an equine isolate of Lawsonia intracellularis, agent of equine proliferative enteropathy. J Vet Intern Med 2010; 24:622-7. [PMID: 20337907 DOI: 10.1111/j.1939-1676.2010.0482.x] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
Abstract
BACKGROUND Equine proliferative enteropathy (EPE) is an emerging disease of weanling foals. OBJECTIVES Describe clinical, hematologic, biochemical, serologic, molecular, and ultrasonographic findings in foals experimentally infected with Lawsonia intracellularis. ANIMALS Eight foals. METHODS Recently weaned foals were assigned to either the challenge (n = 3), the sentinel (n = 3), or the control (n = 2) group. Foals were experimentally challenged via intragastric inoculation of 3 x 10(10)L. intracellularis organisms grown in culture. Each experimentally infected foal was housed with a sentinel foal in order to assess feco-oral transmission. All foals were monitored daily for the development of clinical abnormalities and were weighed once weekly for the duration of the study (90 days). Abdominal ultrasound examination was performed weekly. Feces were collected every other day for 60 days, then weekly for an additional 30 days for the quantitative molecular detection of L. intracellularis. Blood was collected weekly for hematologic, biochemical, and serologic analysis. RESULTS Only challenged foals developed transient clinical signs of EPE consisting of anorexia, lethargy, fever, loose feces, and peripheral edema. Two challenged foals developed transient hypoalbuminemia. Fecal shedding of L. intracellularis was first detected in the challenged foals between days 12 and 18 postinoculation and lasted for 7-21 days. Seroconversion was documented in all challenged foals and in 1 sentinel foal. The remaining sentinel and control foals remained unaffected. CONCLUSIONS AND CLINICAL IMPORTANCE Clinical EPE of variable severity was induced in all foals infected with L. intracellularis. Furthermore, L. intracellularis can be transmitted via the feco-oral route to susceptible herdmates.
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Affiliation(s)
- N Pusterla
- Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California, Davis, CA 95616, USA.
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Pusterla N, Mapes S, Madigan JE, Maclachlan NJ, Ferraro GL, Watson JL, Spier SJ, Wilson WD. Prevalence of EHV-1 in adult horses transported over long distances. Vet Rec 2010; 165:473-5. [PMID: 19850855 DOI: 10.1136/vr.165.16.473] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- N Pusterla
- Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California, Davis, CA 95616, USA.
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Pusterla N, Mapes S, Byrne BA, Magdesian KG. Detection of bloodstream infection in neonatal foals with suspected sepsis using real-time PCR. Vet Rec 2009; 165:114-7. [PMID: 19633325 DOI: 10.1136/vetrec.165.4.114] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Affiliation(s)
- N Pusterla
- Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California, Davis, One Shields Avenue, Davis, CA 95616, USA.
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Affiliation(s)
- N Pusterla
- Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California, One Shields Avenue, Davis, CA 95616, USA
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Leutenegger CM, Madigan JE, Mapes S, Thao M, Estrada M, Pusterla N. Detection of EHV-1 neuropathogenic strains using real-time PCR in the neural tissue of horses with myeloencephalopathy. Vet Rec 2008; 162:688-90. [PMID: 18503069 DOI: 10.1136/vr.162.21.688] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- C M Leutenegger
- Lucy Whittier Molecular and Diagnostic Care Facility, Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California, One Shields Avenue, Davis, CA 95616, USA
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Affiliation(s)
- N Pusterla
- Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California, One Shields Avenue, Davis, CA 95616, USA
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Affiliation(s)
- S Mapes
- Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California, Davis, CA 95616, USA
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Pusterla N, Higgins JC, Smith P, Mapes S, Gebhart C. Epidemiological survey on farms with documented occurrence of equine proliferative enteropathy due to Lawsonia intracellularis. Vet Rec 2008; 163:156-8. [DOI: 10.1136/vr.163.5.156] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- N. Pusterla
- Department of Medicine and Epidemiology; School of Veterinary Medicine; University of California; Davis California 95616 USA
| | - J. C. Higgins
- Loomis Basin Equine Medical Center; Loomis California 95650 USA
| | - P. Smith
- Alamo Pintado Equine Medical Center; Los Olivos California 93441 USA
| | - S. Mapes
- Department of Medicine and Epidemiology; School of Veterinary Medicine; University of California; Davis California 95616 USA
| | - C. Gebhart
- Department of Veterinary Biosciences; University of Minnesota; College of Veterinary Medicine; St Paul Minnesota 55108 USA
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Pusterla N, Mapes S, Wilson WD. Use of viral loads in blood and nasopharyngeal secretions for the diagnosis of ehv-1
infection in field cases. Vet Rec 2008; 162:728-9. [DOI: 10.1136/vr.162.22.728] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- N. Pusterla
- Department of Medicine and Epidemiology; School of Veterinary Medicine; University of California; One Shields Avenue Davis CA 95616 USA
| | - S. Mapes
- Department of Medicine and Epidemiology; School of Veterinary Medicine; University of California; One Shields Avenue Davis CA 95616 USA
| | - W. D. Wilson
- Department of Medicine and Epidemiology; School of Veterinary Medicine; University of California; One Shields Avenue Davis CA 95616 USA
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Mapes S, Rhodes DM, Wilson WD, Leutenegger CM, Pusterla N. Comparison of five real-time PCR assays for detecting virulence genes in isolates of Escherichia coli from septicaemic neonatal foals. Vet Rec 2008; 161:716-8. [PMID: 18037693 DOI: 10.1136/vr.161.21.716] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
Fifty-five isolates of Escherichia coli from septicaemic neonatal foals were used to validate five real-time pcr assays targeting different known virulence factor genes: curli fibre (csgD), ferric hydroxamate uptake (fhuA), type 1A pilin (fimA), aerobactin (lutA) and yersiniabactin (fyuA). A pcr assay targeting a universal sequence of the bacterial 16S rrna gene served as quality control. The pcr assays showed good analytical specificity and sensitivity on the basis of sequencing the pcr products, their lack of cross-reactivity with non-E coli organisms, high amplification efficiency and a limit of detection as low as 25 E coli colony-forming units. There were differences between the detection rates and amplification efficiencies for the five virulence genes. The pcr assays targeting genes csgD, fhuA and fyuA were able to detect all 55 E coli isolates, with gene csgD having the best amplification efficiency. The lowest detection rate and amplification efficiency of the E coli isolates was found for the lutA gene.
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Affiliation(s)
- S Mapes
- Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California, 1 Shields Avenue, Davis, CA 95616, USA
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Pusterla N, Wilson WD, Mapes S, Leutenegger CM. Diagnostic evaluation of real-time pcr
in the detection of Rhodococcus equi
in faeces and nasopharyngeal swabs from foals with pneumonia. Vet Rec 2007; 161:272-5. [PMID: 17720966 DOI: 10.1136/vr.161.8.272] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Affiliation(s)
- N Pusterla
- Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California, Davis, CA 95616, USA
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Affiliation(s)
- S Mapes
- University of California, Davis, California, USA
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Abstract
To date, structure--function studies of aromatase cytochrome P450 (P450arom) have been advanced by point mutation analyses utilizing almost exclusively the human enzyme, in conjunction with computer-generated models of the three-dimensional form of the enzyme based on prokaryotic cytochromes P450. Recent studies have identified duplicated isozymes of porcine P450arom, the gonadal and placental forms of which appear to differ substantially in substrate utilization and inhibitor sensitivity. We present a comparative approach to define regions of P450arom responsible for specific functional characteristics using complimentary DNAs encoding the porcine isozymes. Constructs encoding the native and chimeric porcine and human P450arom enzymes were transiently expressed and activity was assessed using the tritiated water assay. Sensitivity to inhibition by the imidazole etomidate was investigated, and P450arom expression was assessed by immunoblot analysis. All constructs yielded active P450arom, suggesting that exchanging entire structural elements does not preclude catalytic function. The activity of the gonadal isozyme was shown to be inhibited by etomidate at concentrations 185 and 300-fold lower than those required to induce a similar inhibition of the placental and human enzymes, respectively. In contrast, there was only a two-fold difference in the sensitivity of the gonadal and placental isozymes to inhibition by CGS16949A. Analysis of chimeric constructs indicated that the sensitivity to etomidate was associated with residues in the B, B' and C helices of the gonadal P450arom encompassing only one of six putative substrate recognition sites. Additionally, sensitivity to etomidate was not correlated with enzyme activity among the chimeric enzymes. Therefore, it appears that residues of the porcine gonadal P450arom that are responsible for etomidate binding may be distinct from those involved in substrate recognition and metabolism. These data support the notion that a comparative approach employing the use of chimeric enzymes provides a useful tool in directing point mutational analysis to determine residues important in inhibitor and perhaps substrate recognition of P450 enzymes such as P450arom. These studies are currently in progress.
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Affiliation(s)
- A Conley
- Department of Population Health and Reproduction, School of Veterinary Medicine, University of California, Davis, CA 95616, USA.
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Mapes S, Corbin CJ, Tarantal A, Conley A. The primate adrenal zona reticularis is defined by expression of cytochrome b5, 17alpha-hydroxylase/17,20-lyase cytochrome P450 (P450c17) and NADPH-cytochrome P450 reductase (reductase) but not 3beta-hydroxysteroid dehydrogenase/delta5-4 isomerase (3beta-HSD). J Clin Endocrinol Metab 1999; 84:3382-5. [PMID: 10487714 DOI: 10.1210/jcem.84.9.6105] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Biochemical studies suggest that 17,20-lyase activity, and thus efficient synthesis of androgens by human P450c17, requires both reductase and the accessory protein cytochrome b5. Since the human and primate zona reticularis (ZR) secrete androgens, the expression of these proteins, and of 3beta-HSD, was investigated by immunocytochemistry in the adrenal cortex of the mature rhesus macaque. Cytochrome b5 expression was restricted to the cells of the ZR which appeared deficient in 3beta-HSD. However, both P450c17 and reductase were evident throughout the zona fasciculata. These data provide essential evidence in support of a functional role for cytochrome b5 in the regional control of 17alpha-hydroxylase and 17,20-lyase activities of P450c17 and thereby adrenal C19 steroid secretion by the primate adrenal gland.
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Affiliation(s)
- S Mapes
- School of Veterinary Medicine, University of California, Davis 95616, USA
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Abstract
The spectra of six tenors were analyzed at high pitches, F4 to B4. Because of the wide separation between harmonics, formant frequencies could not be extracted in the traditional way. Rather, an analysis-by-synthesis technique was used to match the spectra of a model to the measured spectra, using parameter optimization. Results suggest that tenors maintain their first formant frequencies well above the fundamental for all vowels except [u]. The purpose of this seems to be to distribute the acoustic energy between harmonics 2, 3, and 4 rather than to boost the fundamental. Tuning the first formant to the fundamental is a technique used effectively by sopranos but seems to be deliberately avoided by tenors in order to preserve a male quality.
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Affiliation(s)
- I R Titze
- Department of Speech Pathology and Audiology, University of Iowa, Iowa City 52242-1012
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